When I think of the name "Tragic Kingdom," I think of an entire park full of attractions based on Disney's saddest films, such as The Fox and the Hound, Old Yeller, Up, Bambi, and possibly my own movie.
The only problem with this one is the fact that they are planning on adding a Mary Poppins attraction to the UK pavilion, so if her voice is utilized in that attraction, it would be somewhat distracting to simultaneously hear her voice inside Spaceship Earth.